Process of making stoppers



June 10, 1930.

Filed Jan. 12, 1928 mwzrv TOR. JeanBroad/zurst ATTORNEY.

Patented June 10, 1930 UNITED STATES PATENT OFFICE JEAN BROADHURST, OFNEW YORK, N. Y., ASSIGNOR OF ONE-HALF TO STANLEY J. STANLEY, OF NEWYORK, N. Y.

PROCESS OF MAKING STOPPERS Application filed January 12, 1928. SerialNo. 246,285.

This invention relates to a process of making stoppers having particularreference to stoppers for use in connection with test tubes, bottles orother containers used particularly in laboratories and hospitals.

In common practice, use is generally made of raw cotton as a stopper orplug for test tubes, bottles and other containers, such stoppers orplugs usually being fitted to the containers at the time of making. Inso making these stoppers, a quantity of raw cotton appropriate to thesize of tube or bottle is obtained and is twisted or rolled by hand tosuch size as to properly fit within the mouth 13 or neck of thecontainer. It is very obvious that this practice has a great manyobjections, chief among which is that the stopper must be ofapproximately the same size as the mouth or opening of the tube orcontainer 29 with which it is used requiring the exercise of skill inselecting the requisite amount of material in making and shaping thestopper. Should too greata quantity be used, the stopper will be of suchsize as to necessitate discarding it entirely or to involve remaking andreshaping it, or to compress too tightly or compactly the materialthereof when being forced into the tube or bottle, whereby the latter istoo completely sealed to allow the tree passage of air, steam or vapornecessary in many of the routine procedures for which such plugs orstoppers are used, such as the cultivation of bacteria and the heatingand sterilizing of containers and culture media. On the other hand,should the quantity of material taken be too small, a stopper ofinsufficient size will result and will. drop into the bottle or tube.Furthermore, the time required in this cumbersome practice renders thesamehighly objectionable.

It is the primary object of the present in-' vention to provide astopper of such character as to be adaptable to tubes or bottle mouthsof various sizes, which will effectively seal the container with whichit is used against the ingress of bacteria, dust or other foreignbodies, yet which will possess a degree of perviousness such as willpermit air, steam or vapors to pass therethrough. Stoppers possessingthese characteristics are adapted particularly for use in connectionwithbottles, flasks, tubes or the like wherein there are contamedliquids, chemicals, culture media or other matter of like nature formaking dilucapable of withstanding flaming Without detracting from theefficiency of the stopper or affecting the degree of porosity of thelatter.

A still further object is to provide a stopper and process by means ofwhich the stoppers may beproduced by extremely simple operations, at lowcostand at great saving of material, and wherein the stoppers soproduced retain their shape and effectiveness notwithstanding repeatedor continuous usage.

', In the drawings forming part of this speck fication Fig. 1 is a sideelevation of a blanktrom which the stoppers of my invention may he made,

Fig. 2 is a side elevation of one of the blanks l prior to the treatmentin accordance with my invention,

Fig. 3 is an end view of the blank shown in Fig. 2,

Fig. 4 is a longitudinal section taken through blanks shown in Fig. 2and illustrating the first stop in my improved process,

Fig. 5 is a sectional view illustrating a form or mold for carrying outthe shaping recess, I Fig. 6 is a side elevation showing tlie plug T3 orstopperat the completion of the process, and

F ig. 7 is a fragmentary sectional view showing the application of myimproved stopper'to the neck of a bottle or test tube.

In the accomplishment of the objects set forth, use is made of paper,wood, or fiber pulp formed or rolled substantially cylindrical in shape,the fibers of which may be matted in the several layers and may bedisposed parallel or otherwise to the axis of the roll. The blank thusformed is out transversely entirely through at such places as willproduce a plug or stopper of the desired length, such plugs beingrepresented at 8 in the drawings. In their initial form as thus cut, theplugs are truly cylindrical, and in order that the stoppers be adaptableto bottle necks or tubes within a varied, though limited range of sizes,the plugs are shaped to a taper toward one end. This is accomplished bysubjecting one end of the cylindrical fiber stopper or blank tomoisture. The application of moisture to the stopper end may beaccomplished by subjecting the same to a body of liquid, permitting adrop or more of liquid to engage the stopper end, or the process may beeffectively carried out by subjecting the stopper end to a jet or sprayof steam, vapor or moist air, while, again, the reduced end of a moldfor shaping the stopper may be moistened in any preferred manner so thatthe stopper end will be subjected to moisture upon being applied to theform.

The blank with its end thus moistened is placed or slightly forced intoa form 9 of substantially frusto-conical shape and remains so positioneduntil properly shaped. The drying of such shaped plugs may be carriedout naturally, or, if desired, more rapid drying may be effected bysubjecting the forms containing the stoppers to the action of heat or ablast of warm air, or by applying warm air to the shaped butincompletely dried stoppers. The drawings illustrate the application ofmoisture to the plug and by dipping or touching the plug end to aliquidcontained in a pan or trays 10, but it will be understood that themoistening process may be carried out in other ways as above suggested.The mold 9 shown in the drawings is of conventional form, and it will beunderstood that apparatus for shaping the stoppers may take forms otherthan that de scribed and illustrated.

The moistening of one end of the blank saturates all fibers immediatelyadjacent to that end, and pressure brought about by compressing the endas by applying the mold or form, slightly mats or compacts the moistenedportion, the compression, however, is insufiicient to destroy porosityof the moistened port-ion, nor does it seal or render the treated endthereof impervious.

When dry, the stopper or plug will be found to retain the substantiallytrusto-conical shape, as the moistening and drying operations havepermitted the plug end to become set, and the plug thus becomespermanently shaped in accordance with the form to which it has beensubjected.

In practice, it will be found that plugs or stoppers constructed inaccordance with the foregoing description will prove highly effective inthe associations with which its uses are adapted. The plugs areextremely easy to handle or manipulate both in the applying andwithdrawing operations, and when placed in the neck or mouth of thebottle or tube will effectively close the same against dust, bacteria orother contamination from outside sources, yet permits steam, vapors orair to pass through to the extent desirable in laboratory and hospitalpractices.

By forming the plugs in substantially the manner shown, plugs of a fewgiven sizes are adaptable to tubes or bottles having necks or openingsvarying in diameters.

Having thus described my invention, I claim:

1. The process of making stoppers, consisting of subjecting an end of acylindrical porous body to moisture and tapering of body toward themoistened end.

2. The process of making stoppers, consisting of subjecting an end ofporous roll to moisture and tapering the roll toward the moistened end.

3. The process of making stoppers, consisting of subjecting an end of aporous pulp body to moisture and tapering the body toward the moistenedend.

4. The process of making stoppers, consisting of subjecting an end of a.porous body to moisture and compressing the same in a tapered mold untilshaped or set.

5. The process of making stoppers, consisting of rolling a porous sheetinto cylindrical form, moistening one end of the cylim der and insertingthe moistened end into a form or mold of smaller diameter than thecylinder.

In testimony whereof I afiix my signature.

JEAN BROADHURS'I".

